Warning device and system for flame failure



Oct; 22, 1968 w. .1. HARDESTY 3,407,369 I WARNING DEVICE AND SYSTEM FORFLAME FAILURE 2 Sheets-Sheet 1 Filed Jan. 17, 1967 INVENTOR. William J.Hardes f y 2 a a/$515M W m Wm m I.

llllll wrrrlam HIS ATTORNEYS 3,407,369 Patented Oct. 22, 1968 3,407,369WARNING DEVICE AND SYSTEM FOR FLAME FAILURE William J. Hardesty,Delmont, Pa., assignor, by mesne assignments, t Tale-Flame, Inc.,Latrobe, Pa., a corporation of Pennsylvania Filed Jan. 17, 1967, Ser.No. 609,886

11 Claims. (Cl. 335-156) ABSTRACT OF THE DISCLOSURE A warning device forflame failure employing a thermally-energized electric magnet and amagnetic contact plate to be magnetically held in a forward position bythe magnet upon heat-induced energy thereto. An operating stem supportsthe contact plate for moving the plate into and out of engagement withthe magnet.

The illustrated embodiment of the invention utilizes a thermostatic orthermal means which has a pilot flame part that may be used with a mainheating burner for a hot water boiler or other apparatus that is to beheated by a fluid type of fuel, such as gas, oil and the like. Thethermal means employed may be a commercial means, such as provided byHoneywell or Robertshaw-Fulton Controls Company, see for example, theGrayson unit TS-7 sold by Robertshaw-Fulton. Such a means employsthermocouple metals for generating a small thermionic current when it isheated by the flame of a burner to energize a holding electro magnet.Make and break electrical switch means is used with thermal means toprovide a warning signal when the flame goes out through deenergizationof the electro magnet and to reset the thermal means when heat is againapplied thereto. The switch means is manually moved to an open andresetting position and, upon release after a resetting operation,remains in an open position until the electro magnet is deenergized torelease a hold plate and close switch contacts.

The device of the invention may be used to give warning to the occupantsof a dwelling or building of the failure of a heating agency andparticularly, of a flame type of heating agency, so that immediate stepswill be taken to remedy the deficiency and promptly reinstitute properoperation of the heating medium. It will be appreciated that failure maybe due to clogging of the fuel line, a blast of air, insuflicient fuelor insuflicient oxygen for supporting the flame.

Brief summary of the invention Heretofore, it has been customary toemploy thermostatic controls employing a thermocouple and an electromagnet for the purpose of shutting-off the supply of fuel to a mainburner or heating element if, for example, the pilot flame fails. Thishas the disadvantage that unless periodic inspections are being made ofthe boiler or other means being heated, that the householder or buildingmaintenance man has no indication of the failure until the adverseeffects, for example, lack of heat, are, after a period of time, evidentto him. The present invention deals with an alarm or warning apparatuswhereby immediate indication of flame or heat failure is given.

It has thus been an object of my invention to provide a thermaloperating device that will immediately transmit a warning signal uponthe failure of a heating unit or the like;

Another object has been to devise a new and improved device forutilization in connection with a heating means, such as a fuel burner,which can be reset for each operation of the burner and will be releasedto close switch of and showing the contacts and energize an alarm systemupon a failure of the burner or the extinguishing of its flame;

A further object of the invention has been to devise a.

simple, eflicient, effective and inexpensive thermal electrical switchdevice for giving warning of the failure of a flame or heat source;

These and other objects of the invention will appear to those skilled inthe art from the illustrated embodiment and the claims.

Description of the drawings In the drawings, FIGURE 1 is an explodedview in elevation and partial section of parts employed in con structingan operating unit or device in accordance with the invention;

FIGURE 2 is a vertical view in elevation on the scale parts of FIGURE 1in an assembled relation; in this view, a pilot part of the unit hasbeen omitted for simplicity of illustration;

FIGURE 3 is an enlarged vertical sectional view in elevation of the unitof FIGURE 2 showing the parts in a released or alarm giving operatingposition.

FIGURE 4 is a vertical sectional view on the scale of and of the unit ofFIGURE 3 showing the parts in a preliminary resetting position, such asis manually accomplished when, for example, a pilot flame has beenrelit;

FIGURE 5 is a vertical sectional view in elevation on the scale ofFIGURES 3 and 4 showing the relative positions of the parts of the unitafter a release of the resetting means and after the thermal means hasenergizeda holding magnet to automatically retain the unit in its resetposition during the proper functioning of the heating means, such as aflame;

FIGURE 6 is a reduced somewhat diagrammatic side view in elevationshowing a mounting closure in section and an operatively connectedelectrical alarm circuit or system for the device;

And FIGURE 7 is an end section in elevation on the scale of and of theoperatively mounted device disclosed in FIGURE 6, but with the alarmcircuit omitted.

Detailed description FIGURES 6 and 7 show an operating system orapparatus employing the invention. In this connection, a mountinghousing is shown provided with an outer closure part 11 and anangle-shaped inner mounting part 12 which is enclosed by the part 11.The mounting housing defines an upper burner compartment A and a lowercompartment C within which a device 10 of the invention may be mountedfor convenient operation. The part 12, as shown particularly in FIGURE6, has an upright or vertical plate portion 12a that may be secured to awall or structural support member by threaded bolts or screws 13; italso has a bottom, outwardly-projecting horizontal shelf portion 1212which defines a partition between the chambers A and C and serves as amount for a pin-like or cylindrical thermal element containing part 18that supports a pilot burner 19 at its end. An angle-shaped member 12cis shown secured, as by welding, to the shelf portion 12b for removablysecuring the outer closure part 11 in position thereover by means ofmetal screws 14. The thermal part 18 is carried Within an angle-shapedbase or support part 15 which is shown as having a mounting hole 15atherethrough. A mounting lug projects downwardly from the shelf 12bsomewhat intermediate of its width to serve as a mounting for the part15. In this connection, a threaded bolt or set screw 15b may be insertedthrough the hole 15a into threaded engagement with the mounting lug 120(see FIGURE 7).

As shown particularly in FIGURE 1, the burner base or support part has athreaded gas or fluid fuel inlet fitting 16 projecting therefrom toreceive an internally-threaded female coupling 17a of a gas or fuelsupply line 17. The line 17 may extend to a suitable source, forexample, to a meter connection of a home. The fuel supplied by the line17 enters the base support part 15 and passes through the thermal part18 to the pilot burner 19. Although not shown, a main burner and a wateror other type of heating coil may be mounted in the compartment A, withthe main burner located adjacent the pilot burner 19.

A somewhat flexible, copper-core, heat conductor line 20 is conductivelyconnected to the part 18 and extends from the part 15 and has a slidablemale coupling fitting 23. As shown particularly in FIGURE 1, the fitting23 has a wrench flat 23a and a male threaded end portion 23b forcooperating with internal or female-threading 28aof sleeve end or socket28 of a fitting 27 that is mounted on a front enclosure disk or flange26. The end of the heat conductor line 20 is provided with a terminalplug end 21 to which its copper core is secured and with a washer 22that cooperates with the fittings 23 and 27.

As shown particularly in FIGURES 3 and 4 of the drawings, the terminalplug end 21 is adapted to fit within the open end of the socket 28 ofthe fitting 27. Both the plug end 21 and the socket 28 are of a highlyheat conductive metal, in order that micro current generated by theapplication of heat energy to thermal elements of the part 18 will betransmitted along the conductor line 20, through the plug end 21 and thepart 27 to a U-shaped electro magnet 30. The magnet is secured to theflange or closure disk 26 and made an integral part of the fitting 27.The poles of the magnet 30 may be suitably wound with copper conductorwire 31 so as to pick up the current generated by heat energy andenergize backwardly-projecting contact faces or ends 30a of the magnet30. The fitting 27 has an external threading 27a to removably-receive amounting nut 29 which as shown, for example, in FIG- URE 3, is employedto secure the fitting on an outer or secondary, hollow front housing 40.

The electro magnet 30 projects backwardly within a 'hollow or shell-likefirst, inner or primary front housing 25 and is secured in position withrespect thereto by a turned-in front rim edge 25a of the housing thatengages the end closure disk or flange 26. The inner or first housing 25as well as the outer or second housing 40 may be of a suitablenon-magnetic, electrically-conductive material, such as copper,aluminum, or brass.

The outer or second housing 40, also of hollow shape, has a front flangeor turned-in rim 40a which fits over the front rim edge 25a of the innerhousing 25 and is removably-secured in place by the nut 29 to projectbackwardly beyond a closed back end wall 25b of the housing 25 andreceive a front end portion of a back housing 42 therein. The 'backhousing 42 is also of hollow construction, is of a non-conductivematerial, such as resin, wood, etc., and has a mounting portion ofreduced diameter 42a that is adapted to be removably-secured endwise inposition Within the outer front housing 40 in abutment with the back endof the inner housing 25 by set screws 41.

An operating stem 36 is slidably-positioned for axial movement withinthe closed back end wall 25b of the inner front housing 25 and its frontend carries a magnetic contact or metal hold plate or disk thereon. Amagnetic part or member as mentioned herein, is a member which is ofiron or other suitable material that is subject to magnetic holdingattraction, such as exerted by energization of the electro magnet 30.

The operating stem 36, as shown in FIGURES 3, 4 and 5, extends at itsback end portion into a front chamber portion of the hollow back housingand cooperates with a reset means in the nature of a manual push oroperating stem 47 that is operatively-carried for sliding or axialendwise movement within the back end portion of the back housing 40. Theoperating stem 36 is also of a good electrically conductive metal, suchas brass, copper or aluminum, and preferably the former. The back end ofthe stem 36 carries an integral or secured-on disk or mounting flange 37and a first switch contact means in the form of a flange or disk 37a ofa good electrically conductive metal. A good electrically conductive setscrew 37b having a flat head end is employed for removably-securing thefirst contact switch means 37a on the stem 36 in abutment with theflange 37. Electric current is carried from a connector means orterminal, such as a threaded binding screw and washer assembly 51,through the housing 40- to the housing 25, and from the housing 25through the stem 36 and the set screw 37b to the switch contact 37a.

A second switch contact means is provided by a radially ortransversely-inwardly-projecting, annular, peripheral rim or ledge 45aof a partition member 45 that is located at an intermediate positionwith the back housing 42. The partition member 45 of goodelectrically-conductive material is shown with its centrally-backwardlyolfset back wall or flange 45b resting on an annular ledge 420 of thehousing 42 and as having its annular rim or ledge 45a adapted to beengaged by the first switch contacting means 37a in a make and breakrelationship. Electrical current connection is made to the second switchcontact means 45a by a connector means or terminal 50, such as athreaded binding post and washer assembly, which projects through thewall of the housing 42 and into threadedengagement within the partitionmember 45. It will be noted that the wall 45b of partition 45 has acentral opening therethrough to axially-slidably position the reset ormanual push stem 47 and limit the backward position of such stem incooperation with a front stop or disk-like flange 48 on its front end.The flange 48 is adapted to normally cooperatively engage the back endof the operating stem 36 through the agency of the flattened head of theset screw 37b (see FIGURE 3 It will be noted that the reset or push stem47 has a second or back stop limit flange or projection 48a forengagement with the inner side of a back closure end wall 42b of thehousing 42. At this time, the front flange 48 will, as shown in FIGURE3, be in engagement with the back end of the operating stem 36 (seeFIGURE 3), and electrical connection will be made between switchcontacts 37a and 45a. This represents the normal back position of theparts of the device when no heat energy is being applied to the part 18for electrically-energizing the electro magnet 30.

Resilient or spring means is provided within the back housing 42 fornormally urging both the operating stem 36 and the reset means or pushstem 47 to their back positions, at which time, closed switch contacts37a and 45a transmit electric current between terminal assemblies 50 and51 and also, at which time, magnetic contact or hold plate 35 iswithdrawn from engagement with the electro magnet 30 (see FIGURE 3). Thespring means comprises a forward spiral spring 38 that resists axialcompressing force and is operatively-positioned along or about theoperating stem 36 to, at its forward end, abut the back end wall of theinner housing 25 and, at its back end, abut the disk 37 carried by theoperating stem. The spring means also comprises a second spiral spring49 that resists axial compressing force and is operativelypositionedalong or about the reset or push stem 47 to abut between the back end ofthe partition part 45 and the front face of the back stop or limitflange 48a.

In operating the device, it will be noted that its normal position isthat disclosed in FIGURE 3 when the pilot burner 19 is not lit. To resetthe device, the push stem 47 is manually pushed forwardly against theresiliency of the springs 49 and 38 to move the operating stem 36forwardly and cause the magnet plate or disk 35 to engage the contactfaces 30a of the electro magnet 30. Manual force is retained on theoutwardly projecting push stem 47 until the burner 19 has generatedsufficient heat in the part 18 to electrically-energize the magnet 30.As long as the heat is maintained, the magnet 30 holds the disk 35 inengagement therewith and the operating stem 36 in its forward positionof FIGURE 4. At this time, the manual force on the resetstem'47 will bereleased and it will then return to the position of FIGURE 5. It will benoted that the switch contacts 37a and 45a are out of engagement and noelectrical current flows to the alarm system shown in FIGURE 6.

However, if the gas supplied to the burner 19 should fail or the oxygensupply should become insufiicient, such that the flame or heat producingmeans goes out, then the electric current supplied by the part 18 willcease and the magnet 30 will release the contact or hold disk 35. Atthis time, the spring 38 will then return the operating shaft 36 fromthe position of FIGURE to the position of FIGURE 3 to cause current toflow between terminals 50 and 51 and connected electrical lines or leads50a and 51a to a warning means 55. In FIGURE 6, a suitable source ofelectric current, such as battery B, is shown connected through thedevice in such a manner that when the switch contacts of the device areclosed, a continuous warning signal will be given to the warning device55 in the form of an electrically-operated bell or other electricallyenergized warning means. When the pilot light is not in use, anauxiliary switch 56 in the electric circuit may be opened. It will benoted in FIG- URE 6 that the unit 10 is removably-maintained withinlower compartment C by a pair of support arms 57 and 58 which are ofangle-shape and are removably-secured to a side of the housing part 11by bolt and nut assemblies 59, and in such a manner, that the reset stem47 projects below the lower arm 58 and the housing 11 for manual push-inresetting operation.

As to FIGURES 6 and 7, the housing part 11 may be slid backwardly overthe inner or positioning part 12 after the latter part has been securedon a structural support or wall. The housing part 11 can thus be readilymounted and dismounted for inspection of the chambers A and B by meansof the metal screws 14.

Although the invention has been described from the standpoint of anillustrative embodiment, it will be apparent to those skilled in the artthat various changes, modifications, and adaptations may be made withoutdeparting from its spirit and scope as indicated by the claims.

I claim:

1. In a device for warning of flame failure having a hollow non-magneticfront housing and employing a thermally-energized electric magnetmounted within a front end portion of the front housing, a magneticcontact plate to be magnetically held in a forward position by themagnet upon an application of heat-induced energy thereto, an operatingstem projecting axially backwardly from and supporting the contact platefor moving it into and out of engagement with the magnet, and means atthe back end portion of the front housing for slidably-supporting theoperating stem to project backwardly therefrom, the improvement whichcomprises: a hollow back housing having a front open end portion forcooperative mounting with respect to the back end portion of the fronthousing, said back housing receiving "a back end portion of theoperating stem therein, a first switch contact means mounted on the backend portion of the operating stem, a second switch contact means withinsaid back housing in cooperative alignment with said first switchcontact means, reset means extending backwardly from the back endportion of the operating stem and operatively-mounted within andextending outwardly through a back end portion of said back housing, andspring means within said back housing and cooperating with the operatingstem and said reset means for normally urging the operating stem to aback position at which the contact plate is out of engagement with themagnet and said first switch contact means is in closing engagement withsaidsecond switch contact means, and said reset means cooperating withthe operating stem for moving it forwardly against the resiliency ofsaid spring means until the contact plate is in engagement with themagnet and said first switch contact means is out of closing engagementwith said second switch contact means and for holding the contact platein engagement with the magnet until the magnet is energized by theapplication of heat-induced energy to magnetically-maintain said contactplate in engagement therewith.

2. In a device as defined in claim 1 wherein an electric alarm system isconnected to said switch contact means for Warning of flame failure whensaid switch contact means is closed by de-energ' ation of the magnet andthe operating stem is returned by said spring means to its backposition.

3. A device as defined in claim 1 wherein, said first switch contactmeans is a conductive disk mounted on the operating stem, and saidsecond switch contact means is a conductive annular abutment projectingradially within said back housing for cooperatively-receiving saidconductive disk.

4. In a device as defined in claim 3 wherein, said reset means comprisesa push stem having a radial projection cooperating with said backhousing for limiting the maximum outward movement of said push stem withrespect to said back housing; and said spring means comprises, a firstspiral spring operatively mounted along the back end portion of theoperating stem within the front end portion of said back housing andbetween the back end portion of the front housing and a front side ofsaid conductive disk, and a second spiral spn'ng operatively positionedalong said push stem within the back end portion of said back housingand between a back side of said annular abutment and the back end ofsaid back housing.

5. A device as defined in claim 4 wherein said push stem has a front endportion for normally engaging a back end of the operating stem.

6. A device as defined in claim 5 wherein said front end portion of saidpush stem is a position limiting flange.

7. In a device as defined in claim 1 wherein, a second hollow fronthousing encloses and removably positions the non-magnetic front housingtherein and projects backwardly therefrom to endwise-receive the frontend portion of said back housing therein, and securing means is carriedby the back end portion of said second front housing forremovably-securing said back housing in position therewithin.

8. In a device as defined in claim 7 wherein, said back housing is anon-conductive material, electrical connector means extends through saidback housing to said second switch contact means, the first and secondfront housings and the operating stern are of electrically conductivemetal, said first switch contact means is electrically connected throughthe operating stem and the first front housing to the second fronthousing, and electrical connector means is secured to the second fronthousing.

9. A device as defined in claim 1 wherein, a mounting housing isprovided for securing to a building member and defines an upper burnercompartment and a lower housing compartment for the device, and means iscarried by said lower compartment and cooperates with the front housingand said back housing of the device to securely mount the device withinthe lower compartment.

10. A device as defined in claim 1 wherein said first switch contactmeans is an electrically conductive disk secured on a back end of theoperating stem, said second switch contact means is an electricallyconductive partition within said back housing and through which saidreset means slida'bly extends, said reset means comprises a push stemhaving a flange to engage the back end of the operating stem, and saidflange is adapted to engage within said partition to limit backwardmovement of said push stem outwardly with respect to said back housing.

11. A device as defined in claim 1 wherein, said first 8 ReferencesCited UNITED STATES PATENTS 3,109,906 11/1963 Abendroth 335-470 5BERNARD A. GILHEANY, Primary Examiner.

H. BROOME, Assistant Examiner.

